My above-referenced U.S. Pat. No. 3,783,850 relates to a method of obtaining an automatic ignition advance as a function of the speed of rotation of an internal combustion engine such as employed in an automobile. The method is characterized in that, linearly or not depending upon the desired control of advance, a voltage V.sub.1 proportional to an angular offset .alpha., measured as an angle between a reference position of the engine flywheel and a variable position of the same flywheel, is compared to a voltage V.sub.2 proportional to the rate of change of rotation of the engine. Voltage V.sub.1 increases with angular offset .alpha. from the given reference position and when it coincides with voltage V.sub.2, there is produced an ignition pulse which triggers the ignition spark at that instant. As a result, a relationship is established by means of parametric ratios of voltages V.sub.1 and V.sub.2, between angular offset .alpha. and the engine R.P.M., which is made to correspond with the relationship dictated by the desired advance curve.
The device for implementing the above-described method of the patent is characterized in that it comprises a voltage generator for producing a voltage V.sub.1 proportional to the angular offset .alpha., which is applied to a first terminal of a pulse generator, and a tachometric generator for producing a voltage V.sub.2 proportional to the speed, which is applied to a second terminal of the pulse generator. In turn, the pulse generator produces a pulse controlling the ignition whenever voltage V.sub.1 coincides with voltage V.sub.2, consideration being given to a proportionality factor.